1. Field of the Invention
This invention relates to a circuit arrangement for igniting at least one gas discharge flash tube of the type having at least two main electrodes and connected in parallel with a chargeable flash capacitor.
2. Description of the Prior Art
The British patent application No. 36843/75 discloses a circuit arrangement for igniting at least one gas discharge flash bulb (flash tube) having two main electrodes which are arranged in parallel with a chargeable flash capacitor and an electronic switch and are connected to a voltage generator which supplies ignition voltage pulses, the electronic switch likewise constituting a gas discharge path.
A circuit arrangement of this type is characterized, in particular, in that the blocking diodes in the discharge circuit which are usually required in parallel ignition and which be designed for high blocking voltages and high forward currents can be eliminated, and that ignition voltage pulses of both polarities can operate on the flash tube. Particular advantages are obtained if a plurality of flash tubes are operated in series as, in this case, one of the flash tubes can itself be used as an electronic switch in the form of a gas discharge path.
However, when the above-described circuit is operating with one of the conventional ignition transformers, as disclosed in the German published application 2,422,201 which corresponds to U.S. Pat. No. 3,838,358, as a voltage generator, the following problem can occur. In order to ensure that every tube ignition reliably leads to a flash discharge, the flash capacitor must apply a voltage ("anode voltage") which is a multiple greater than the theoretically required burning voltage.